[chef] guards for include_recipe

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I've got a recipe where I try to download a .deb file but don't know if the
file really exists on the other side.
If the file is not present I have to build the package from scratch.

I've got a recipe which handles the build itself but I'm unable to include/not
include  it based on the result of the download attempt.

I can't use File.exists?() because this is evaluated at compile time and there
the file is not present. For resources I can use guards, but these are not
supported for include_recipe.

How would I handle this scenario and avoid wrapping the build in a bash script
or add my guard to every resource in the build recipe!?